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  • Carbohydrate utilization of Erwinia amylovora in vitro
    31-34.
    Views:
    153

    Nectar is a multi-component aqueous solution that promotes bacterial multiplication. The concentration of nectar in plant flowers is not stable since it is under the influence of environmental conditions, especially free moisture and relative humidity. Experiments were conducted with "artificial nectar" and directed along two lines: (1) determination of the optimal concentrations of carbohydrates for the growth of E. amylovora development (2) consumption of different carbohydrates besides basic sugars.

    Solutions of "artificial nectar" were prepared in different compositions by changing the dominance of basic sugars (fructose — glucose —sucrose) in proportions of 2:1:1, 1:2:1, 1:1:2 and between concentrations of 10-0.6% (diluted with Basal minimum broth) in order to determine optimal conditions for the development of E. amylovora.

    At a basic sugar concentration of 10% bacterial multiplication started and continued until I log degree (from 106 to 107 cfu/ml). At concentrations of 5% and 2,5 % cells developed with nearly the same kinetics (from 106 to 8x107 cfu/ml and from 106 to 9x107 cfu/ml, respectively). Multiplication was more pronounced and nearly the same at concentrations of 1.2 % and 0.6 % (from106 to 2x108 cfu/ml). At a basic sugar concentration 30% total sugars bacterial multiplication did not occur, while at 20 % it was negligible, not measurable photometrically.

    At minimal concentrations of F, G, S (between 1-0.1 %) bacterial cells were still able to multiply, producing organic acids from sugars.

    Our study showed that E. amylovora requires only a small amount of sugars (0.1%) for multiplication (acid production) while high concentrations inhibit multiplication. There was a negative correlation between sugar content and cell density. The optimal range of sugar concentration was at about 1%.

    Effect of "less frequent carbohydrates" to E. amylovora multiplication was also determined using the API 50 CH strip. We could provide information on utilization of 39 carbohydrates by the bacterium at different categories as follows: Not utilized-, Slowly and weakly utilized-, Slowly and completely utilized-, Quickly and completely utilized carbohydrates. We suppose that carbohydrates that belong to the latter two groups could play an important role as nectar components in promoting E. amylovora multiplication in the blossoms of pome fruit trees.

  • Investigation of some production factors on yield and quality of dry beans
    83-88.
    Views:
    114

    The correlation between plant density and yield average shows that the volume of yield increases in varieties of large and medium-size seeds up to a plant density of 285-400 thousand/ha, after which it declines.

    On the basis of the results, yield averages at plant densities of 285-334 thousand plant/ha are 0.17 t/ha higher than those achieved at low density (200 thousand plant/ha).

    High levels of potassium fertilizer did not enhance the yield of dry beans. With adequate-water supply the high level of potassium decreased the number of pods and seeds per plant compared with a basic level of fertilizer, which could ensure 2.5 t/ha yield.

  • Nutritional quality, fruit shape and relationships among exotic and local Capsicum pepper genotypes in Uganda
    33-39.
    Views:
    328

    Twenty-one hot pepper genotypes comprising of local (15) and exotic (6) types (C. annuum, C. frutescens and C. chinense) were characterized for selected fruit traits after propagation in a glasshouse at the Makerere University Agricultural Research Institute Kabanyolo in Central Uganda using a completely randomized design with three replicates. Ripe fruits were harvested and analyzed; traits evaluated were all significantly different at P<0.05 with variations in quality attributes. The genotype OHA-B305-10 had the highest ascorbic acid content (128.86 mg/100 g) and is recommended for improvement of both local and exotic genotypes targeting the fresh market. Genotypes CAP0408-12 and UG2 WE0511-22, with highest total soluble solids (16.17 ºBrix) and dry matter content (28.59%), respectively should be used in improvements for industrial use or processing to products such as chilli powder or flakes. BRS-M205-04 with highest titratable acidity (1.04%) can be used in enhancing shelf life of genotypes with low titratable acids as well as for the fresh market. In spite of the intraspecific relationships among genotypes, significant differences were observed in their quantitative traits. These genotypes will, therefore, be useful in improving the quality of hot pepper fruit in Uganda.

  • The effect of Ferbanat L nano-fertilizer on the growing of Petunia x grandiflora ’Musica Blue’
    107-109.
    Views:
    242

    During our experiment, the effect of Ferbanat L concentrations were examined by Petunia x grandiflora ‘Musica Blue’ production. The leaf and shoot length, number of flower buds, diameter of flowers, and the date of appearing the first buds were measured. The solution of Ferbanat L in 0.1 % concentration was the most effective on shoot length (21.7 cm). Remarkable increase was observed by the other treatment groups as well comparing to the control group (5.6 cm), the plants treated with solution of Ferbanat L 0.2% (16.5 cm) and 0.3% (14.4 cm) had significant effect as well. The nano-fertilizer had not positive effect on the other examined parameters as leaf and flower size, number of flower buds or chlorophyll content. The culture period shortened five days.

  • Determination of chlorophyll content in case of peach leaf curl disease (Taphrina deformans) with spectral analysis
    49-52.
    Views:
    288

    One of the most important conditions of high quality fruit production is the early detection of hytopathologycal infections. The most dangerous disease of peach (Prunus persica) is the Taphrina deformans, which causes serious damages mainly in the years where the weather condition is cool and wet. In this study, healthy and naturally diseased leaves by peach leaf curl were investigated in the laboratory of University of Debrecen, CAAES, Institute of Water and Environmental Management. Both of hyperspectral measurement and the values of spectrophotometer shown the chlorophyll content of diseased leaves were lower than the healthy samples. Based on the experiments the water status of investigated leaves established the infected leaves contained more water in their tissues.

  • Assessment of apple varieties based on consumer judgement on their fruits of organic production for fresh consumption
    87-90.
    Views:
    202

    The lack of information is often cause of the insufficiency of attributes being developed and appears on the new commodity characterising its utility. Neither own nor other information is presented. For improving this handicap, we endeavoured to praise apple products grown by biological methods and explain their properties as taste, skin, colour, consistency, and size. In addition, we explore the relation between general impression and the individual properties. The scrutiny starts with collecting of primary data on 9 samples taken from biologically grown apple varieties kept over 60–90 days in a store and offered to the consumers. The test is based on an organoleptic assessment (records are registered in a questionnary). The individual judgements are processed and coefficients of correlation between the traits (taste, skin, size, colour) calculated. The validity of the mathematically proved relations is considered to be decisive judging the preferences in consumption of fruits.

  • Efficacy of N-phenylphtalamic acid in some Solanaceae species
    89-91.
    Views:
    113

    : N-phenylphthalamic acid — Cl4H1 1 NO3 (Nevirol 60 WP) was successfully used for enhancing yield in some important vegetable crops namely, tomato (Lycopersicon esculentum), chilli (Capsicum annuum) and brinjal (Solanum melongena) of Solanaceae. Aqueous sprays with 0.2% and 3.0% significantly enhanced fruit production in chilli and tomato respectively. On the other hand, various treatments in brinjal failed to enhance yield significantly. The increase in yield in both tomato and chilli is largely due to increase in the number of flowers and fruit-set percentage.

  • Illumination-Independent Reflectance Information Acquirement for Leaf Water Potential Measurement on the Example of Satsuma Mandarin
    75-79.
    Views:
    116

    Mandarin fruit sugar content can be increased when subjecting the satsuma mandarin tree (Citrus unshiu MARC. var. satsuma) to moderate water stress by mulching during the period of active sugar accumulation, thereby fruit quality improvement can be realized. In the frame of the precision agriculture production system, a non-destructive measuring method development became necessary based on remote sensing, field spectroscopy and image analysis, to be able to measure the degree of water stress. Large amount of visual information have been recorded at ground level, in near infrared, red and green channels by a false color digital camcorder designed specially for remote sensing applications. A method have been found to be able to calculate the absolute reflection of mandarin leaf surface by comparing leaf reflectance with known reference target reflectance, thereby established the basis of further studies in this topic. Leaf absolute reflection can be measured reliably, under variable natural illumination at field conditions. Functional correlation can be searched between visual information and leaf water potential measured by PMS pressure chamber.

  • Rootstock evaluation in intensive sweet cherry (Prunus avium L.) orchard
    7-12.
    Views:
    202

    During 2000 and 2007, rootstocks of different vigor have been tested in a high density sweet cherry orchard with 'Vera '® and 'Axel'® cultivars at 4 x 2 meter row and plant distance. Trees are trained to Hungarian Spindle with permanent basal branches; in the alley way naturally grown grass is managed by mowing. The first considerable fruiting was in 2004. Every year we measured trunk and canopy parameters of the trees, productivity and fruit size. Our conclusion is that the rootstocks considerably affected the growth, precocity, as well as tree and orchard productivity, fruit weight of sweet cherry cultivars, but these rootstock effects are modified by cultivars, except for growth vigor. According to our results Cema, SL 64, and Bogdany are vigorous rootstocks, moderate vigorous are MaxMa 97, Pi-Ku I , and Tabel® Edabriz, Gisela® 5 and Prob are dwarfing rootstocks. Besides the precocious Gisela® 5 also mahaleb rootstocks CEMA, Bogdany and SL 64 showed considerable precocity, which can be explained by the larger bearing surface to the time of turning to bearing, and a similar or relative large density of burse shoots on fruiting branches. Cumulative yield of 'Axel'® was the highest on Bogdany and on Cerna, contrary to Gisela® 5, which produced only 50% of the previous ones. Cumulative yield of 'Vera'® was the highest on SL 64, and no significant difference was found, compared to trees on rootstocks Cema, Bogdany and Pi-Ku I . Cumulative yield production of trees was smaller on Gisela® 5, Prob, Max Ma 97 and Tabel® Edabriz rootstocks. Corresponding to the literature data of yield efficiency calculated on TCSA basis was highest on Gisela® 5 rootstock. but the efficiency calculated on canopy volume of 'Axel•® trees was similarly high on CEMA and Bogdany, and that of 'Vera'® trees relatively high on CEMA, Bogdany, SL 64 and PiKu I rootstocks. When calculating orchard efficiency al spacing 4 x 2 meters (1250 tree/ha), we received highest yield values on Bogdany, CEMA, SL 64, and PiKu I rootstocks, with large fruit weight. Rootstocks also affect fruit weight. We measured the largest fruit weight on trees on Bogdany.

  • Comparison of the biogenic amine content of traditional and bio-wines
    115-118.
    Views:
    128

    There has been a growing tendency in organic farming in recent years, in which organic grape growing and the production of bio­wine are also significant. The literature on bio-wine is rather limited, that is why we consider it really important to contribute to the data. As a result of the special conditions in organic farming we can expect bio-wines to have a different composition of nitrogen compounds from that of traditional wines. Biogenic amines could thus specially characterize bio-wines. In our research we compared the biogenic amine content of wines produced using organic methods and of those where traditional procedures were used. Our measurements have proved that it is not possible to clearly distinguish bio-wines from wines produced with traditional methods on the basis of amine content.

  • Fruit injury in organic fruit production and its relationship to brown rot caused by Monilinia spp.
    7-9.
    Views:
    204

    In a two-year Hungarian study, the temporal progress of brown rot incidence and various injury types were studied in organic fruit orchards and the relationship between brown rot and injury types was determined. Results showed that brown rot reached an almost 20% incidence level in both years. Total injury incidence reached up to 5.3 and 19.8% in the two years. In all cases, insect injury incidence was the highest among injury types in most assessment dates. Incidence levels of other injury types (bird injury, mechanical injury and other  injury) began to increase, but none of those reached levels >4%. Pearson’s correlation coefficients showed that  brown rot incidence correlated significantly with the incidence of insect injury. In addition, brown rot incidence and the incidence levels of bird injuries was also significantly correlated. High injury and brown rot incidence levels suggest further improvements on organic fruit protection.

  • Disease incidence of Monilinia fructigena coupled with codling moth damage and mechanical injury in an organic apple orchard
    55-57.
    Views:
    210

    In a two-year-study, disease incidence of Monilinia fructigena were quatified and the importance of certain fruit wounding agents was determined. The first infected fruits were observed at the beginning of August in 2011 and 2012. Disease development was continuous until fruit harvest in both years. Pre-harvest yield loss caused by M. fructigena amounted on average 26.3% in 2011 and 40.4% in 2012 by fruit harvest. All infected fruits were injured mainly by mechanical injury factors and codling moth (Cydia pomonella). In this study, the most important wounding agents were codling moth and mechanical injury factors in organic apple orchards. In both years, our results showed that 65-75% of the infected fruits were damaged by codling moth in organic apple production. Moreover, 5-15% of the infected fruits were mechanically injured in the two years. Our results indicated that most of the damaged fruits fell on the orchard floor before harvest and they became an important secondary inoculum source of M. fructigena. Biological and practical implications of the results are discussed.

  • New evaluation method to detect physiological stress in fruit trees by airborne hyperspectral image spectroscopy
    37-40.
    Views:
    163

    Nowadays airborne remote sensing data are increasingly used in precision agriculture. The fast space-time dependent localization of stresses in orchards, which allows for a more efficient application of horticultural technologies, could lead to improved sustainable precise management. The disadvantage of the near field multi and hyper spectroscopy is the spot sample taking, which can apply independently only for experimental survey in plantations. The traditional satellite images is optionally suitable for precision investigation because of the low spectral and ground resolution on field condition. The presented airborne hyperspectral image spectroscopy reduces above mentioned disadvantages and at the same time provides newer analyzing possibility to the user. In this paper we demonstrate the conditions of data base collection and some informative examination possibility. The estimating of the board band vegetation indices calculated from reflectance is well known in practice of the biomass stress examinations. In this method the N-dimension spectral data cube enables to calculate numerous special narrow band indexes and to evaluate maps. This paper aims at investigating the applied hyperspectral analysis for fruit tree stress detection. In our study, hyperspectral data were collected by an AISADUAL hyperspectral image spectroscopy system, with high (0,5-1,5 m) ground resolution. The research focused on determining of leaves condition in different fruit plantations in the peach orchard near Siófok. Moreover the spectral reflectance analyses could provide more information about plant condition due to changes in the absorption of incident light in the visible and near infrared range of the spectrum.

  • Storage ability and differences of carrot varieties defined by firmness changes measured with new non-destructive acoustic method
    37-40.
    Views:
    174

    Carrot production in Hungary is getting more important these days. The condition of the quality insurance is to choose the proper variety of carrot and store on optimal conditions therefore measuring firmness and matter parameters are very important. Four varieties of carrots were measured (Bangor, Olympus, Napa and I3olero). The roots were stored in unsealed polyethylene bags at 4-10 degrees Celsius and 95% relative humidity. The vegetables were measured three times: at harvest, after I .5 months of storage and after four months of storage. The samples were tested by non-destructive acoustic. Stillness measuring method during the 112 days experiment for firmness. In laboratory were measured weight loss, dry material -NO3 and sugar content as an important matter parameters.

    The firmness change as a function of storage time are the following: First part of the storage (after 60 days), the Napa variety changed least in the case of acoustical parameter, at the same time its weight Foss and dry material content were not rise significantly, while its sugar content increased with 50%. The l3olero variety had the highest changes of sugar content during storage. During the second storage period, the softening speed of all samples was increased. The Bolero had the highest average mass loss (32,7%) and NO3 content changes as well. All measurements showed the largest changes for the Bolero variety. The highest percentage of dry material content was found by the Bolero and Napa varieties (18-20%).

    In this experiment, we found that the Bolero variety showed the greatest loss in compressibility during storage. If both firmness and weight loss results are considered, the Napa variety is found to be the most storable variety in sort period. The Bangor variety was found to be the best for long-term storage.

  • Vegetative parameters of sweet cherry (Cerasus avium L.) cultivars in two training systems
    42-45.
    Views:
    258

    Hungarian sweet cherry production has been changed recently. Thanks to the favourable selling prices many new plantations were established in the last years. In the new orchards mainly spindle canopy are trained, although many type of crown forms are used all over the world. In our study slender spindle and bush canopy were evaluated with three cultivars (‘Petrus’, ‘Vera’, ‘Carmen’) grafted on Prunus mahaleb rootstock. Vigor of the 3-4 years old trees showed spectacular differences. The highest vigor with Spanish bush was found for cv. ‘Vera’, but on slender spindle canopy the thickness values were medium. Meanwhile cv. ‘Petrus’ showed the highest trunk thickness with spindle canopy, but the lowest with Spanish bush. On spindle canopy cv. ‘Carmen’ presented the highest ramification ability, but its 2-3 years old twigs started to bald very early, which can be considered an unfavorable phenomenon. Bush canopy still can be described with strong vegetative growth on 3-4 years old trees, as vigor of spindle trees are more moderate.

  • Examination of the apricot variety use and the factors affecting variety use in the Gönc production area
    111-113.
    Views:
    182

    Hungary is a traditional fruit growing country for ages. As fruit sector has a very high hand work request and value added, it has an important role to decrease the elimination of unemployment and the lack of income in the disadvantage rural areas. The study was made in the year of 2009, the studied population consisted of the members of the fruit-grower marketing organization (Gyümölcsért Ltd.), that organizes growing and sales of stone fruits in Hungary. The studied area of this Ltd is in North Hungary. The growers, who filled the questionnaire, were selected random simple sample. Two data collection were used during our research work: primer and secondary data collection. The resources of the primer data-collection were the questionnaires of our empirical survey that have been completed by the relevant information from informal interviews with farmers (who previously filled the questionnaires in). We introduced and analysed the local (county level) and the wider (region level) farming conditions by the secondary data. By the composition of the questions both qualitative and quantitative methods have been used. This current study intends to represent one part of this comprehensive research.We wish to briefly introduce mainly the research results concerning variety use.

  • Organic versus integrated apple growing: I. differences in soil and leaf parameters
    57-60.
    Views:
    185

    The aim our study was to establish whether significant differences in nutrients uptake and quality of soil and leaf exist between organic and integrated grown apples. The study was performed at the orchard Fruit Research Station, University of Debrecen, at Debrecen-Pallag during 2002–2004. Macro and micro elements were measured in soil and plant samples. Analyses of variance of soil nitrogen data indicated highly significant differences between the two management systems (P < 0.001) for each examined nitrogen fraction. Analyses of variance of soil phosphate data indicated significant differences (P < 0.05) between the two management systems for orto-PO4 3– contents. Our data indicated that highly significant differences between the two management systems (P < 0.001) for magnesium, copper, and zinc; while significant differences between the two management systems was at P = 0.007 for calcium. Three year’s data of leaf phosphorus, sulphur and zinc were not shown significant differences between production systems. Nevertheless manganese and copper contents of leaves were higher in the organic orchard compared to the integrated one.

  • The impact of irrigation on the yield and tuber fraction distribution of potato cultivars
    65-70.
    Views:
    122

    Potato is one of the most important plants in human nutrition, it is grown in about 140 countries. As a food, it can be prepared in many ways, it is easily digestable with proteins of high biological value, favourable dietetical-physiological characteristics, high starch content and good taste. An increase in its consumption would be favourable from the dietetical point of view. In Hungary, the growing area of potato has decreased considerably for the last decades and we are lagging behind the Western-European countries regarding yield. The experiments were carried out at the Experimental Site of the University of Debrecen at Látókép between 2002 and 2004. In the large-plot experiment, the yields and the distribution of the tuber fractions were studied for 9 medium early cultivars. The experiment was set up on 50 m2 plots on calcareous chernozem soil. Among the studied cultivars, 3 were of Dutch (Desiree, Kondor, Kuroda) and 6 were of Hungarian breeding ('Góliát', 'Hópehely', 'Kankan', 'Lilla', 'Százszorszép', and 'White Lady'). The experiment was set up in 4 repetitions in a randomized design, two of the repetitions were irrigated while two were non-irrigated.

  • Utilisation of nutrients by cucumber plants oil rockwool substrate
    117-121.
    Views:
    106

    Cucumber production by soil less culture on rockwool substrate in Hungary is an open system regarding its water and nutrient supply. Environmental and economical reasons require the recycling of nutrients of the system. Experiments have been planned in order to estimate the utilisation of individual nutrient elements applied. All around the vegetation period, chemical analyses monitored the depletion of the elements initially administered by sampling the solutions at successive phases from the injection to the overflow. The results have been compared with earlier experiences refering to general rules. It has been stated that the intensity of photosynthesis is decisive in determining the composition of the overflow. The less changes are observed during the period of frequent watering.

    The absorption of the nutrient elements varied between 25-51% deperiding on the individual elements. The differences are significant. Further examinations are needed in order to clear:

    • which are the main elements of technology, which are decisive in utilisation of nutrients
    • what are the possibilities of the secondary utilisation of nutrients.
  • Identification of plant taxons by isoelectric focusing
    65-67.
    Views:
    158

    Differences were demonstrated in esterasei coenzyme pattern of some essential oil producing plants belonging to the Apiaceae family — fennel (Foeniculum vulgare Mill.), angelica (Angelica archangelica L.), lovage (Levisticum officinale Koch.), dill (Anethum graveolens L.), coriander (Coriandrum sativum L.), anise (Pimpinella anisum L.), caraway (Carum carvi L.) — as well as differences between two varieties of fennel seed by using isoelectric focusing. That method provides quality control in essential oil plants and is suitable to describe isoenzyme pattern characteristic for taxons.

    Based on our findings, isoelectric focusing seems to be suitable for identification and differentiation of different plant samples, providing an easy tool for further processing as well as for breeding.

    Our further aim is to apply that method to differentiate among samples belonging to the same species according to their value of inner content.

     

  • Evaluation of the competitiveness of fresh tomato
    Views:
    158

    The existence of international trade and related trade theory are closely related to competitiveness. The following study focuses on the competitiveness of Hungary, which studies the development of comparative advantage in terms of tomato for fresh consumption among horticultural products. As a consequence, the main objective is whether Hungary has comparative advantage over EU-28 countries in case of fresh market tomato. Data in the study were provided by FAOSTAT database. The study period focuses on results from 2004 to 2019, breaking them down into 5-year (average) cycles. The method chosen was the RCA index group, the most widely recognized and applied index group for calculating comparative advantage. Although Hungary is not a significant vegetable-producing country in Europe, the fruit and vegetable sector accounts for 10-13% of the production value of agriculture. Regarding the results, it can be stated that Hungary does not have comparative advantage in case of tomato products. With respect to values of the tomato sector, the RCA index is in the range of 0<RCA≤1, therefore we have no comparative advantage. Spain and the Netherlands have stable competitive advantage. These countries show weak comparative advantage in each period studied, as the indicator values exceed 1 but do not reach 2.

  • Effect of different starter and foliar fertiliser rates on some compositional parameters of sweet corn (Zea mays convar. saccharata Koern.)
    41-44.
    Views:
    198

    In recent years consumers tend to pay ever greater attention to food ingredients looking for foods with favourable compositional characteristics. Researches nowadays aim to find out what role the different vegetable species play in protection of the human organism. Consumption of vegetables and fruits more times a day plays an important role in this process. The valuable chemical components in plants can eventually be influenced, besides, by environmental characteristics, also by the elements of the production technology applied. Our work aimed to find out what eventual changes occur in the composition parameters of sweet corn (Zea mays convar saccharata Koern.) receiving different NPK fertilizations and top dressed with foliar application of Zn and Mg, destined chiefly for fresh consumption, in response to the treatments mentioned above. The fertiliser rates were compared with the help of the variety Spirit (normal sweet, very early ripening).

  • Effects of Foliar Nutrition on Onion Seed Storage under Modified Atmosphere Packages
    93-100
    Views:
    198

    Modified atmosphere packaging (MAP) and controlled atmosphere storage techniques to reduce the oxygen around the food are largely used for the preservation of fresh produce. There have been great technological advances in this area of preservation, particularly as it refers to improving the quality and shelf-stability of highly perishable food products, such as produce. Two successive winter seasons of 2008/2009 and 2009/2010 were conducted under sandy soil conditions to study the effect of spraying with 12 commercial compounds on onion seeds storage under modified atmosphere packages. Germination percent of seeds decreased in 5°C than storage in room temperature. Germination percent of seeds was gradually decreased with increasing the storage period. Packaging treatments had a significant effect on germination percent of seeds. All the packaging treatments had the higher germination percent than the paper package (control). The highest germination percent after 12 months of storage was recorded for the treatment with non perforated polypropylene in room temperature and polyethylene and non perforated polypropylene in 5°C. Catalase activity decreased with the prolongation of storage period. The non perforated polypropylene package had the highest catalase activity. The treatment with non perforated polypropylene had the highest catalase activity after 12 months of storage in both room and 5°C temperatures. Peroxidase activity of seeds was gradually decreased with increasing the storage period. The highest peroxidase activity after 12 months of storage was recorded in non perforated polypropylene in both storage temperatures.

  • Virus and virus-like diseases of grapevine in Hungary
    25-36.
    Views:
    257

    Viruses and viroids are submicroscopic infectious particles which can cause disease symptoms on grapevine. These parasites are depending completely on the energy metabolism of the plant cell. To enter the host cell plant viruses depend on injuries or on transmission via invertebrates (insects, nematodes, etc.). Viruses are classified by many characters including particle morphology, host range and information content of the genome. At present about 70 viruses including 7 viroids infecting grapevine are known. In single or mixed infections they are potentially detrimental to the quality and quantity of grape production in any growing area of the world. Some viruses can cause severe economic damage in vineyards. In Hungary many important viruses and viroids have been detected in grape. This review summarises characteristics of viruses and the results of detection and characterization of virus and virus like diseases of grapevine in Hungary. The identification of the causal agent, its transmission, geographical distribution and the development of the diagnostic methods are also discussed.

  • Promising white poplar (Populus alba L.) clones in sandy ridges between the rivers Danube and Tisza in Hungary
    113-116.
    Views:
    174

    White poplar is a native stand-forming tree species in Hungary, covering 3.1 per cent of the forested area. More than 70 per cent of the white poplar stands can be found on calcareous sandy sites in the Danube—Tisza region, so they play a significant role in the poplar management of this part of the country. The most important task ahead of Hungarian poplar growers is to improve the quality of poplar stands and plantations based on selecting new clones and cultivars. The growth and yield of four promising white poplar clones was evaluated on a marginal site in central Hungary. The clones `1-1 425-4' (Populus alba x Populus alba), and 11 758' (Populus alba Mosonmagyaróvár 124) seem to be suitable for wood production, while the 427-3' (Populus alba x Populus alba cv. Bolleana) and 422-9' (Populus alba x Populus grandidentata) clones (with decorative stem form) could be better used for tree lines and ornamental plantations.